Buchh, A., K. Gupta, D. Sharma, U. Anwar, M. N. Pandey, and P. Kalra. “Comparative Evaluation of Fentanyl Versus Nalbuphine for Attenuation of Hemodynamic Changes During Airway Stimulation”. International Journal of Research in Medical Sciences, vol. 6, no. 2, Jan. 2018, pp. 632-8, doi:10.18203/2320-6012.ijrms20180312.